This invention relates to disposable diapers. More particularly, this invention relates to disposable diapers having adhesive tab-type fasteners.
Disposable diapers provide substantial advantages in convenience over conventional diapers and commonly have a generally quadrilateral configuration with straight or curvilinear longitudinal edges. Disposable diapers are conveniently secured about an infant by means of adhesive tape tabs which are affixed to the diaper along a longitudinal edge thereof, thus eliminating the need for extraneous fasteners, such as pins. In order to protect the adhesive surfaces of the tape tabs, usually a release sheet is applied over these adhesive surfaces for subsequent removal when the diaper is about to be used. However, such tabs usually project beyond the confines of the diaper to a considerable extent and interfere with the efficient manufacture and packaging of the diaper.
In an attempt to solve the foregoing problems, U.S. Pat. No. 3,776,234 to Hoey proposes to fold the tab over on itself at the diaper's edge and to adhesively attach a portion of the folded-over tab segment to the inside surface of the diaper in order to keep the tab from interfering with the manufacturing machinery and with the folding and packaging operations. This requires that the edge of the diaper backing sheet be folded over to present an attachment surface at the front or inside face of the diaper and a relatively involved tab design is necessary for this purpose. Also, undesirable tearing of the diaper facing fabric may result if such a tab is adhesively attached to the facing fabric of the diaper.
While the present disposable diaper closure systems utilizing adhesive tab-type fasteners having the adhesive surfaces thereof protected with readily removable release strips are relatively convenient to use, such closure systems have the disadvantage that the consumer has to dispose of the release strips when they are separated from the fasteners immediately prior to use. This is an inconvenience to the consumer who is placing a diaper on an infant at about the same time.
In an attempt to remedy the aforesaid disadvantage, U.S. Pat. No. 3,646,937 to Gellert shows a fastening tab which is provided with a release surface permanently attached to a diaper backing sheet at a margin thereof and folded inwardly over the diaper facing. In addition to requiring relatively involved manufacturing manipulations the teachings of Gellert also require special securement means to assure that the fastening tab will not separate from the release sheet prematurely during manufacture and handling of the diaper. According to Gellert, a portion of the tab fastener having a tacky surface also serves as a pull tab for assisting the separation of the tab fastener from the release sheet. Such an arrangement is undesirable, however, inasmuch as the tacky surface on the "pull tab portion" would be rendered relatively less tacky due to finger contact therewith during preparation of the diaper for ultimate use, thus the effective tacky surface available for securely fastening the diaper would be considerably and undesirably reduced.
The present invention, on the other hand, provides a release region on the diaper facing to which is removably attached a free working end of a tab fastener bearing a relatively aggressive adhesive. Finger contact with a tacky surface on the free working end is avoided and the separation thereof from the underlying release region on the diaper facing is facilitated by a pull string segment attached to the free working end.